1. Field
Embodiments of the present invention are related to the field of data encryption and encryption key management.
2. Description of Related Art
Cryptography is frequently used to control unauthorized viewing of sensitive data on a variety of removable media types (e.g., USB flash drives, CD-ROMs, DVD-ROMs) by encrypting the data. However, the encryption (or decryption) key associated with that data is generally possessed by the user. While this allows the user to access their own data and prevents others from using that data without the owner's knowledge, it would not prevent an insider leak as happened in the highly publicized WikiLeaks release. (In that case, the owner of the media was also the source of the release.) Encrypting the information using standard methods would not have blocked the release of the information because the authorized owner (or possessor) of the medium containing the sensitive data would likely also possess the decryption key and therefore would be able to decrypt the contents once outside of the enterprise (e.g., a corporation, a facility, a military unit, etc.).
Prohibiting the use of removable media within an enterprise is one alternative, but this deprives the enterprise of the advantages of being able to quickly move large amounts of information (e.g., physically transporting removable media from one place to another when network connections are comparatively slow). For example, such restrictions have generated a enough of an impact that some military units in the field override these restrictions because the loss of function was deemed to have a greater negative impact than a potential leak might.
Therefore, it would be desirable to have a system that is capable of restricting the disclosure of information by an insider who has authorization to view or use that information. Existing techniques either provide very limited protection against this kind of attack or provide protection in a manner that unacceptably reduces the functionality of the system being protected.